cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A294490 Triangle read by rows: T(n,k) is the number of simple connected graphs on n vertices having independence number k.

Original entry on oeis.org

1, 1, 0, 1, 1, 0, 1, 4, 1, 0, 1, 11, 8, 1, 0, 1, 34, 63, 13, 1, 0, 1, 103, 524, 205, 19, 1, 0, 1, 405, 5863, 4308, 513, 26, 1, 0, 1, 1892, 100702, 135563, 21782, 1105, 34, 1, 0, 1, 12166, 2880002, 7161399, 1576634, 84185, 2140, 43, 1, 0, 1, 105065, 138772607, 652024627, 203380116, 12140094, 274156, 3845, 53, 1, 0
Offset: 1

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Author

Andrew Howroyd, Oct 31 2017

Keywords

Comments

Bivariate inverse Euler transform of A263341. This sequence can be derived from A263341 because the independence number of a disconnected graph is the sum of the independence numbers of its components. - Andrew Howroyd, Feb 19 2020

Examples

			Triangle begins:
  1;
  1,   0;
  1,   1,    0;
  1,   4,    1,    0;
  1,  11,    8,    1,   0;
  1,  34,   63,   13,   1,  0;
  1, 103,  524,  205,  19,  1, 0;
  1, 405, 5863, 4308, 513, 26, 1, 0;
  ...
		

Crossrefs

Columns 2..5 are A243781, A243782, A243783, A243784.
Row sums give A001349.
Cf. A263341 (not necessarily connected).

Extensions

Terms a(56) and beyond derived from A263341 added by Andrew Howroyd, Feb 19 2020